Magical Optiplex 755 upgrade?

[lordshadowhack]

Hello, I was thinking of upgrading my old computer here, its processor is intel core 2 duo, 7 gigs of ram and an HD 7570, for some reason, Im able to run Ultra skyrim everything maxed with an ENB that specifically kills FPS. I've heard of this ENB killing FPS of far better machines than mine.

How my computer does this(playable FPS of 10-20) with this hardware is beyond me.

But im looking for a better GPU.

Im aware that the PSU is unmoddable. I was curious. If I bought a PSU, plugged it in, and connected the GPU to my desktop and the external one to the GPU, can it work?

My optiplex should be able to fit a double slot card the way I have it, its open case too.

Can I run a high end power hungry GPU with this method? An external power supply?

 

[dwatterworth]

You won't get much out of a more powerful GPU as the 755s are stuck in the PCIe 1.1 era. Anything more powerful will most likely be extremely bottlenecked by your CPU / entire platform.

What resolution are you playing at?

 

[lordshadowhack]

You won't get much out of a more powerful GPU as the 755s are stuck in the PCIe 1.1 era. Anything more powerful will most likely be extremely bottlenecked by your CPU / entire platform.

What resolution are you playing at?

right now im at 1776x1000 resolution

So even if I get a more powerful graphics card running, it wont use its full potential?

 

[dwatterworth]

Correct. You would probably max out with the GPU's that don't need any PCIe power power connectors.
Do you have the mid tower / full size 755? I believe you can change the PSU out to an ATX one, the mounting holes on the back of the dell case should match up to normal ATX. I've got a bunch of these 755's and 745's kicking around at work that I cobble together back into working stations. Not that it is needed for the previously listed GPU reasons.

Unless you absolutely can't upgrade to a new platform, I would say your best bet would be to put a used core 2 quads in there. You won't see much performance increase, but 'some' in more demanding titles.

 

[lordshadowhack]

Correct. You would probably max out with the GPU's that don't need any PCIe power power connectors.
Do you have the mid tower / full size 755? I believe you can change the PSU out to an ATX one, the mounting holes on the back of the dell case should match up to normal ATX. I've got a bunch of these 755's and 745's kicking around at work that I cobble together back into working stations. Not that it is needed for the previously listed GPU reasons.

Unless you absolutely can't upgrade to a new platform, I would say your best bet would be to put a used core 2 quads in there. You won't see much performance increase, but 'some' in more demanding titles.

Im curious, what do you mean by max out?

Is there a difference between a powerful GPU that can work purely on the slot, and the one that needs external power? Assuming lets say for example, if a HD6850(AMD) worked, would its power be limited?

And this is the desktop version, sucks lol that I cant do much.

And when I say external psu, I mean buying a psu, plugging it into the wall/outlet, and using it only for the GPU

 

[dwatterworth]

It's possible and easy to rig two PSU's to a system, 1 for the main components and an additional to supplement anything you need. Tons of the guys doing larger bitcoin mining systems that required multiple PSU's to power all the GPU's on a single rig really brought the price down on those setups.

So by max out, I mean a few things:

1. The PCIe 1.1 bus that the 755s have can only transfer 8 gb/s. You mentioned the 6850, which would actually be about the fastest GPU that you would want on a PCIe 1.1 slot, the 6950 above it will be able to process more data than the bus can handle, technically losing performance from it.

2. The platform itself cannot process enough information fast enough to keep a higher end GPU supplied with data to process. For example: You have your AMD 6850 GPU in your machine and it gets XX FPS. Move the same exact 6850 to a more powerful platform, or even go up to a core2 quad (in a limited sense) and you will see XX+Y FPS.
--In a platform limited scenario, in GPU or CPU reviews, you often see a ludicrous scenario such as a pentium system with a R9-290X or GTX Titan installed. That setup makes sure that the GPU is not the limiting performance factor, giving you a direct comparison of the CPU. The opposite also goes, say to test a GPU you see the reviewers pair the card up with a new Ivy Bridge-E 4960X or Sandy Bridge-E 3960X, to make sure the single GPU is most likely the 'weakest' portion of the system.

The GPU needing additional power plugs doesn't necessarily mean it can process more information than the PCIe 1.1 board and your CPU can handle, but the last two generations of cards, anything that does need an extra power connector, is more powerful than your platform can fully handle.

 

[dwatterworth]

Not to say that there is not a lot of life left in your 755, it all depends on the games you are running and at what resolution/detail level you want to be at.

 

[lordshadowhack]

Not to say that there is not a lot of life left in your 755, it all depends on the games you are running and at what resolution/detail level you want to be at.

I checked near the slot and it says pci-e 16.1, what does the 16.1 mean?

 

[dwatterworth]

It means revision 1.1 Pcie slot, X16 slot. So it's a full X16 slot, just the 1.1 revision, with a max of 8GB/S bandwidth.

 

[lordshadowhack]

It means revision 1.1 Pcie slot, X16 slot. So it's a full X16 slot, just the 1.1 revision, with a max of 8GB/S bandwidth.

This optiplex 755 is running pretty smoothly and looks like it will last long enough, is it possible for a 6850 (or maybe even 6950) to run better than my 7570 (excluding power requirements), on this computer?

I probably will get a i3-7 compatible mobo soon too whenever I have that money

 

[dwatterworth]

I think the 6950 would be as high as you would want to go realistically. There are great deals on quality open box or used ones on newegg, amazon, ebay or any other source like that. I've bought a lot of used processors, GPU's, mobos, memory, even SSD's, great way to save cash.